I have no idea HnT.
It looks like you are maybe getting a dependency cycle loop, but if you linked everything in the right way, you shouldn’t.
Does it happen when you open the original rig file? Try it to see but obviously don’t save any animation in the rig file.
If it works ok in the original file, then it is something to do with your animation file.
Try linking it in again to a fresh file (and then appending in any animation that you have already done)
If it doesn’t work in the original file, try downloading the rig file again to see if you have accidentally broken something in there
